Extended Interaction Klystrons with Traveling-Wave Cavities

摘要

Klystrons with extended interaction regions can have a larger gain-bandwidth product and higher efficiencies than conventional klystrons. This study pertains to a new type of extended interaction cavity, consisting of a closed transmission line loop which will support a traveling wave if the loop is properly excited. Two methods of excitation, both using a directional coupler, are described. An electron beam can interact with this traveling wave over part of the closed loop. A general theory of the traveling-wave resonator in the absence of an electron beam is given. The important parameters for interaction with an electron beam are derived. Measurements on an experimental cavity agree very well with theory.